# -*- encoding: utf-8 -*-
# frozen_string_literal: true
module RDF
  class Node
    # Odd case of appending to a BNode identifier
    def +(value)
      Node.new(id + value.to_s)
    end
  end

  class Statement
    # Validate extended RDF
    def valid_extended?
      has_subject?    && subject.resource? && subject.valid_extended? &&
      has_predicate?  && predicate.resource? && predicate.valid_extended? &&
      has_object?     && object.term? && object.valid_extended? &&
      (has_graph?      ? (graph_name.resource? && graph_name.valid_extended?) : true)
    end
  end

  class URI 
    # Validate extended RDF
    def valid_extended?
      self.valid?
    end
  end

  class Node 
    # Validate extended RDF
    def valid_extended?
      self.valid?
    end
  end

  class Literal 
    # Validate extended RDF
    def valid_extended?
      return false if language? && language.to_s !~ /^[a-zA-Z]+(-[a-zA-Z0-9]+)*$/
      return false if datatype? && datatype.invalid?
      value.is_a?(String)
    end
  end
end

class Array
  # Order terms, length first, then lexographically
  def term_sort
    self.sort do |a, b|
      len_diff = a.length <=> b.length
      len_diff == 0 ? a <=> b : len_diff
    end
  end
end